Double Clutching is like a normal shift, but w/a pause in neutral, clutch out, in, then shift to the next highest gear.

Granny shifting is just a smack talking term for driving slow, made famous from the Fast n Furious movie.

Speed Shifting is overrevving the engine & upshifting w/o using the clutch. Hard on trannys. useful w/broken ankle & drivin urself 2 hosp.

Certain sorts of high end engines/transmissions require double clutching to shift from one gear to another. Double clutching syncs the speeds of the clutch plates and keeps the gears from mashing. Has nothing at all to do with granny shifting, which means